This study examines the role of the primary care physician in the identification and management of children with Attention Deficit Disorders. ADD represents one of the most frequent mental health problems diagnosed in children, and the family physician is usually the first health professional to be consulted when problems with inattention or hyperactivity are suspected. However, minimal information is available about the actual practices of primary care physicians in evaluating children with ADD. In fact, family physicians may be at a distinct disadvantage in attempting to diagnose ADD since they often must rely on limited data of questionable validity. A basic hypothesis of this study is that ADD children managed by primary care physicians may not necessarily present the same type and severity of symptoms as children seen in psychiatric clinics and tertiary medical centers. This hypothesis, if true, has far-reaching implications for diagnostic decision-making in the primary care setting and for appropriate training for pediatricians and family practitioners. To investigate the diagnostic procedures of family physicians, children in the practices of ten physicians will be studied on a prospective basis. Physicians will identify children between the ages of 6 and 12 years with presenting problems of attention deficits and hyperactivity. These children (plus a group of age-matched controls) will be given a battery of psychological tests; behavioral ratings will be obtained from parents and teachers; and a formal psychiatric interview will be used to arrive at a DSM-III diagnosis. These data will be used to define the specific behavioral and cognitive characteristics of the children identified by the family physicians. In Phase II, a parallel epidemiologic study will be carried out and will include all 6 to 12 year olds in the schools in the same geographic regions served by the physicians who participated in Phase I. This will establish prevalence estimates for attentional and hyperactive symptoms and for the diagnosis of ADD in order to determine whether the pattern of behavior problems identified by physicians are representative of the population of children in that area. Child characteristics associated with ADD (e.g., conduct disorders, learning disorders0 will also be compared in children identified in each referral setting (i.e., school and physician office), and the factors that contribute most significantly to diagnosis in each setting will be examined.